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equipment. The Survcadd thickness averages for the non prime farmland fields west of the pit in <br />February 2008 show 7.10 inches for the average of Lift A and 17.40 inches of Lift B. Using 80% <br />of the soil sample average to obtain a stripping average for the area, this results in 5.7 inches for <br />Lift A and 13.9 inches for Lift B. Therefore, the total average stripping thickness for the combined <br />Mixed Topsoil ( Lift A and Lift B) is 19.6 inches. The expected range is from 8 inches to 38 inches. <br />The mine foremen and operators will be trained on the stripping of the mixed Lift A & B, and will <br />know to stop the removal when coarse fragments have a rise from less than 10% volume in Lift B <br />to material that has significantly higher coarse fragments (20-25%). In some cases, bedrock will <br />be encountered at the end of Lift B in the non prime farmland areas. <br />An additional amount of suitable subsoil, which is basically the Bench 1 overburden material, will <br />be stripped and placed as shown on Map 2.05.4-4. The Benson West property basically has <br />already been backfilled with a minimum of 30 inches of this material. The Lloyd property will <br />receive a minimum of 30" of this material and the WFC property will receive a minimum <br />thickness of 24" of this Bench 1 material. This backfilled Bench 1 material was tested in April <br />of 2008 for the eastern area of the Morgan property which was exposed that time, and the results <br />showed that it meets the suitability criteria. For the purposes of the volume calculations, the <br />suitable subsoil material on the Benson West is assumed to be 30" in thickness, and Lloyd property <br />is 30" and the WFC property will be 24" in thickness. These amounts allow a minimum of 48" total <br />suitable medium on the Benson and Lloyd properties and 44" on the WFC property. <br />From the 1998 soil survey, the Bench 1 suitable material is differentiated from the bottom of Lift <br />B (which is the C soil horizon) by greater percentage of coarse fragments. The C horizon (at the <br />bottom of the combined Lift A & B) generally has less than 10% coarse fragments and the Bench <br />1 material has from approximately 15% to 30%. Lower material with higher coarse fragment <br />amounts is considered overburden and will be placed below the suitable subsoil material. The mine <br />foreman and the equipment operators will be trained to differentiate these levels of coarse <br />fragments. <br />(Revised June 2008) 2.04.9-27